How to pretty print nested dictionaries?

Leveling Up: pprint & PyYAML

pprint: For those who like it deep

The pprint module's PrettyPrinter comes with depth control. How deep you go with dict is now in your hands!

from pprint import PrettyPrinter
# Here's something shady
shady_dicts = {'Level 1': {'Sub-Level1': {'Sub-Sub-Level1': 'You have reached the core'}}}
pp = PrettyPrinter(depth=2)
pp.pprint(shady_dicts)
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• PrettyPrinter lets you customize pretty printer instances.

PyYAML: Make it comprehensible for humans

import yaml
# Intricate family tree? No problem!
family_tree = {'Grandpa': {'Father': {'You': 'Composer of YAML'}}}
print(yaml.dump(family_tree, allow_unicode=True))
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• yaml.dump() transforms the dictionary to human-readable YAML format.
• Use allow_unicode parameter to enable support for emojis, because who doesn't love emojis!

Advanced pretty printing techniques

Handling custom objects

json.dumps() offers a neat little trick for custom objects:

# Ever tried fitting a square peg in a round hole?
print(json.dumps(my_custom_dict, indent=4, default=str))
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• default=str will handle non-serializable objects your dict might throw at it.

Recursive pretty print function

For mental gymnasts out there, you can use recursion for nested dictionaries:

# Because running in circles is fun!
def pretty_print(d, indent=0):
    for key, value in d.items():
        print('\t' * indent + str(key))
        if isinstance(value, dict):
            pretty_print(value, indent+1)
        else:
            print('\t' * (indent+1) + str(value))

pretty_print(nested_dict)
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• Recursive function adapts to any dict depth.
• \t gives consistent indentation, making code as clean as a freshly washed laundry.

Sorting keys

Because life is too short for finding keys in a dict:

# Let's organize that mess!
print(json.dumps({'b': 2, 'a': 1}, indent=4, sort_keys=True))
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• sort_keys=True will put everything in order, making it easier to find the keys in the literal dictionary of your data.